perl: Replace non-existent function call _() with _g()

[hertzog@debian.org:
 - Fix the same mistake in scripts/dpkg-shlibdeps.pl ]

Closes: #708607

Signed-off-by: Raphaël Hertzog <hertzog@debian.org>
Signed-off-by: Guillem Jover <guillem@debian.org>

debian/changelog

@@ -141,6 +141,9 @@ dpkg (1.17.0) UNRELEASED; urgency=low
   * Improve dpkg-maintscript-helper behaviour in “Multi-Arch: same” packages
     by arch-qualifying package names read from the environment. Also add
     a warning about this potential problem in the manual page.
+  * Fix usage of non-existent _() function in multiple places of the Perl
+    code. Thanks to Lincoln Myers <lincoln@netapp.com> for the patch.
+    Closes: #708607
 
   [ Updated programs translations ]
   * Fix typo in Spanish translation of update-alternatives.

scripts/Dpkg/File.pm

@@ -39,12 +39,12 @@ sub file_lock($$) {
     if ($@) {
         warning(_g('File::FcntlLock not available; using flock which is not NFS-safe'));
         flock($fh, LOCK_EX) ||
-            syserr(_('failed to get a write lock on %s'), $filename);
+            syserr(_g('failed to get a write lock on %s'), $filename);
     } else {
         eval q{
             my $fs = File::FcntlLock->new(l_type => F_WRLCK);
             $fs->lock($fh, F_SETLKW) ||
-                syserr(_('failed to get a write lock on %s'), $filename);
+                syserr(_g('failed to get a write lock on %s'), $filename);
         }
     }
 }

scripts/dpkg-shlibdeps.pl

@@ -143,7 +143,7 @@ my $control = Dpkg::Control::Info->new();
 my $fields = $control->get_source();
 my $bd_value = deps_concat($fields->{'Build-Depends'}, $fields->{'Build-Depends-Arch'});
 my $build_deps = deps_parse($bd_value, build_dep => 1, reduce_arch => 1);
-error(_('error occurred while parsing %s'), 'Build-Depends/Build-Depends-Arch')
+error(_g('error occurred while parsing %s'), 'Build-Depends/Build-Depends-Arch')
     unless defined $build_deps;
 
 my %dependencies;